Machine for undercutting



Patented Mar. 7, 1922.

4 SHEETS-SHEET l.

F. L. 0. WADSWOBTH.

MACHINE FOR UNDERCUTTING.

APPLICATION men APR.13,.1912. RENEwEn Nov.24.1919.

Patented Mar. 7, 1922.

4 SHEETS-SHEET 2.

F. L. 0. WADS'WORTH.

MACHINE Foa UNDER'CUTTING.

APPLICATION FILED AFR4 I3, I9I2 RENEWED NOV. 24,1919.

F. L U. WADSWORTH.

MACHINE FOR UNDERGUTTING. APPLICATION man APn.1a.l912. nENEwEu nov. 24.1919.

@ www?,

Mmm M LJNITED STATES PATENT OFFICE.

JEFFREY naNUFAcTUmNG COMPANY, or COLUMBUS, axioma comomTmN F OHIO.

MACHINE FOR UNDERCUTTING.

Specifica tion of'Lettcrs Patent.

, Patented Mar. 7, 192,2.

Application led April 13. 1912, Serial No. 690,486. Renewed November 24, 181i). 'Serial H0. 340,239.

ing acutting apparatus laterally in a. direc4 tion V substantially A parallel .to the face o1' breast of. the material.

One of 'the objects of the invention-is to provide a, mechanism by which the under- \cutting can be effected more rapidly than by the earlier means with which I am acquainted, this being accomplished by pro riding mechanical elements which give to the cutting devices'two simultaneous movements, one a. forward movement in the direc tion of the cut, and the other an angling movement in the plane of the cut, so that 'the cutter element, as a whole. is advance@ not in parallel with itself but with an oscillatin or,v zigzag movement` by reason of whici the cutting element is presented at each instantV at a new angle to the surface or the line of the cut.

A\nother object of the invention is to provide simple and eiiective mechanism whereby such forward oscillatingv or zig zag movementV of the cutter element may be automaticallyand continuously maintained without attention on the part of the operator or machine runner. i

v Other objects and advantages of the invcn'- tion will appear in connection with the di scriptio'n'of the operation indicated and in connection with the description of the particular mechanisms which are shown as adapted to carry out this operation.

l'n the accompanying drawings Figs. l, 2 and 3 arc diagrammatic views illustrating the positions which the cutter bar of the machine successively occupies in carrying ont the method of zig zag" cross-undercutting; Fig. 4 is a plan view of one form of machine adapted to the practice of the method; Fig. 5 is a front side elevation of said machine; Fig. 6 is a cross section on the line 6-6, Fig. 4; Fig. 6 is a rear View of the machine in Fig. 4 with parts broken away; Fig. 7 is) a perspective view of the t ached cam in said machine; Fig. 8 is ai plan view of cportion o'f a, second form of machine adapte to the practice of the method; Figs. 8*, 8" and 8c are detailed views showing the sliding retarding rope wheel alidfits ad-'60 iuncts, detached; Fig. 9 is a. rear end elevationof the machine shown in Fig.r8; "F ig. 10 is a partialvdiagrammatic side elevation showing a part of the train of drivinggears-f employed in said'm'achine'; Fig. 10, shows 65 the swm ing pinion-carrying frame fdc y ig. 11 .is a vplan view of a third form of machine b` .which the cross undercutting operations illustrated -in Figs. 1 and 2 may be automatically carried out; Figs. 70 12 and 13 are respectively rear and front end elevations of the njiachine shown in'Fig.- 11, the rear elevation being partly in cross sec; f tion on the line 12 of Fig. 11; and is a rear side elevation of said mac "ne, 75. Fig. 15 shows one ofthe worms onthc armarture shaft and its worm wheehdetched; Figs. 16 and 17.are detailed views of the clutch lever shown in Fig. 14, detached.

.I will first describe the,general method 80, of carrying;r out my zig zag operation of 'e cross-umlercutting and then describe more in detail the construction of the various mechanisms illustrated for the automatic performance of the method. Y

Referring to Fig. 1. 1 indicates the' face or breast of the mineral in which it is. desired to cut a 'slot or kerf eithernt the bottom of the l,yein, or at the top, or ut some intermedia-te point between the to!) and bottom. This slot or kerf. is comparirtively narrow and machines of various ty Jes have been designed for cutting it by eit er" a. continuous or intermittent movement of the cutter har or element..` This invention relates particularly to the operatic of continuousmachines inwhich the cuttin is performed by parts or elements whichfw ile' performing their cutting operation, are fed continuously forwardly -in` a direction sub- 10o stantially parallel to the face or breast, 1, of the mineral. The most usual type of cutter bar which is used in this class of machines is one in which the cutting elements or bits" nic-secured to an endless chain, indicated in Figs. 1, 2, and 3 by the reference numeral, 2; this chain being mounted on two sprocket-4 wheels, the outer one 3 revolvin freely inl bearings at the end ofthe cutter ar 4, and the inner one 5 being mounted under the 1 10 frame 6 of the machine and positively driven by suitable mechanism carried bythe said frame. In's'ome types of these machines'- such as dagrammaticall shown,v for .exam' ple, in F igs;l 1 and 2-t e cutterbar 4 and frame 6 are rigidi vsecured together so that they move forwar as aunit'.; In other ty es of machines-such as diagrammatica ly shown in Fig. 3-the cutter bar 4 is pivoted on themachlne frame 6 so that it has an independent' angling movement with respectV to said fram.

In the revious .use of both types of machine it `as been the ractioe. tov advance. the cutter bar 4 paralle to itself durin the pro lof the cross undercutting, sai cutte)` a'Lbeing angled or'inclined with respect to the mineral face 1 only-occasionally, and in general only at certaln times, 'as at the beginning and end of thejcut (where the undercutting is being carried on 1n comparatively narrow-rooms o r stalls), or at4 times when the cutter bar encounters a hard spot or lump of foreign material ini-the vein and it becomes necessary to attack such spots at a newiangle offcut` Y .f

According to the present method of'oper ation there is imparted to the 'cutter bar. 4- a continuously' oscillatory or swinging movement first in'one direction and then in the other whilethe machine als. 'whol'e is being fed forward in the direction oflcut. Thus, starting'with the position indicated at A, Fig. 1, themachine frame is given an angular swinging movement 1n a contra-cloekwise/direction-as viewed froqm above-whle it is advanci'n forward 1n the direction of the arrow 4is'simultaneous contra-clbckwieand Y iorward advancing movementiilg continued until the machifi'e has reachedthe position indica-ted ,l at

B. The direction of the angling movement is then reversed so that the cutter barele-4 ment 4--and in this case the whole machine frame also-:.'wings ina clockwise drection while it is advancing from the position B to the position C. The direction of angling movement ofthe cutter bar element 4 is then again reversed -so that it swings once more in a vcontra-clockwise direction while advancing to the position D. These simultaneously angling and` forward movements of the parts' carrying the cutting mechanism are continued as the machine moves along the face or'breast l of the mineral until the machine reaches the end of its cut. By thus comhining the regular forward movement of the machine with the swinging or angling movement of the cutter harelement the linc of engagement between the cutting bits and the kerf face of the cut is continually varied and the cutting proceeds more rapidly than is possible when this lino of engagement is maintained parallel to ilsellA Wy improved method is vconsiderable period 'of time.

In order to. equalize the work and rate of cuttingin equal intervals of time the rate -at which the machine frame is fed or,

ward along the mineral face 1` is further varied in such'manner that the amount of mineral removed from the ker while the machine is moving from the position A' to the position B gir from the corresponding positions Cv to orE t-oF) will be Sub stantially equalfto the amount..of mineralremoved from the kei-f whilethe machine frame is moving from the position VB-'to C l(gor from the` corresponding position D to To do thisit is necessary to make the rate of forward feed mifch less when theA cutter barvis angling in a contra-clockwise direction than it is when the said bacia angling in a clockwise direction; and the change in. the rate .of forward feediwill'.

vary with and depend u on the extent of the angling movements o the cutter -bar in the two irectionsl Thus, in Fig'. l, the

rate of forward feed must be so varied as to4 cause a given point 7 on the machine frame to move from the position a to the osition b (or from 'the corresponding positions c to d or e tof) while the machine frame is angling contra-clockwise, and in the same interval of time move from the position b to the position c (or from the cor ing position d to the position e) whi e the cutter bar is angling clockwise. The amount of material cut from the kerf while the'machine is moving from the"position A to the position B is indicated byl the shaded area a b' vof Fig. 1 while the amount of material cut out in the movement o f the machine frame from the position C is indicated y the reversely shaded area b c'.'

It is obvious that in order to equalize the Work of cutting during the two successive cycles of machine movement these two areas must be suhstanl tially equal, and the rate of forward feed must be so varied in passing from one cycle to the next as to secure the desired equality in tire amount etmaterial cut during substantially equal time periods of operation. This determines the ratio of the distance n-; to the distance b--c.

The ratio between the distances a-b and b-c will depend upon the extent of the angulai'* movement of the cutter bar while the machine is moving through the distance from a to c. This is clearly shown in Fig. 2 in which the angular swing of the. cutter har is very much greater than it is in.. the' operation illustrated in Fig. l4 lu this rase osition B to the.-

ros

l tothe the rate of forward movement during the clockwisefswing ofuthe cutter bar -as lfor example the movement from the position B osition C-must be very much greater t an the rate of forward movement during the reverse swing o'f the cutter bar, which occurs while the machine is moving .from the position C to the' position D. As in the previous ca 1e .the equalization of the work of cutting during successive cycles of operation re ulres-that the amount of kerf material in t e shaded area b c of Fig. 2

shall be substantiall equal to the amount linthe adjacent sha ed area c cl'; and in order tot secure this equality the ratio between the forward movements b-c and C--rl must be veryr considerably greater than the ratio between' the corresponding distances required to secure said equality of cutting action under the conditions of machine movement illustrated in ig. 1. i

Fig. 3 yshows diagrammatically a type of continuous side 'undercutting machine in which the cutter bar element 4' is pivotally mounted on the machine frame 6 so that the said cutter bar element can be angled withoutl correspondingly moving the` machine frame. In such types of machines the frame proper is usually mounted on tracks 8 laid parallel to the face or breast 1 of the mine eral. In carrying out my method otzig zag cross-under cutting with -this type of machine one proceeds exactly as with machines of the type conventionally shown in Figs. 1 and 2. That is to say the cutter bai 4 is given a uniform swinging or angling movement in a contra-clockwise direction while the machine with the attached cutter bar is being fed forward parallel to thc face of the mineral from the position A to the position B; and then the angling movement of the cutter har is reversed and given a uniform swinging movement in a clockwise direction `while the machine is being advanced from the position B to the position C. Substantial equality of cutting duty during these two successive cycles ,ofjmovement is secured by making the ratio between the distances af--b and b-c such that the amount of material removed from the kerf during the first cycle is substantially the same as the amount removed during the second cycle. The process of zig zag cross-undercutting can be carried out with any suitable shortwall or long-wall machine having capacity for angular adjustment of its cutter har. hy providing such machine with a variable forivard feed. and regulating the feed movements and the angling movements by hand in such manner as to slow down the forward movement of the machine while it is being angled contra-clockwise and accelerate the forward movement of the machine while it is being angled clockwise; these two movements being so controlled with respect to .cessive equal intervals of timex But it .is

,preferred to;avoid the necessity for such iand control and regulation by providing an 'automatically acting mechanism for properly timing and co-regulating the simultaneous anglin and forward movements of thecutter ar and machine frame during the successive cycles of operation. Several forms of semi or artially automatic machines by means o which the zig zag method of cross undercutting can in part be carried on are shown yin the comgenion application, Ser. No. 678,567i filed ebruary 19, 1912. The present application shows three other forms of machine b) which said method' can be carried out in a completely automatic manner;

In the first'construction shown in Figs4 and 5 the machine frame 6 is provided with a suitable base for its support directly on the floor of the mine. The cutter bar 4 may be of any suitable construction and is provided with the endless cutter chain 2 carryingcutter hits. 9. The cutter chain is carried by the idle sprocket 3 at the outer end of the cutter bar 4and bv the driving sprocketg in the bottom hollow portion of the machine framet'. The chain may be driven by any suitable motor, the drawings showing diagrammatically an electric motor 1f) mountedi'on top of the frame 6, although a compressed air' motor or other prime mover may be used. rIfhis motor is arranged with its drivingr shafts transverse to the main frame and cutter bar extension. Said driving shaft is provided at one end with a pinion 11 meshing with spur gea;1 12 which rotates on `a stud secured to fthey motor frame.` Secured to the gear 12 is a tates in a bearing 15 mounted on the machine frame. On the inner end of this sleeve is a. mitre gear 16 which meshes with a corresponding gear 17 on the upper end of a vertical shaft 18 which passes down through the top plate of the machine frame G and carries at its lower end a spur pinion 19 engaging with the master gear 2() on thc shaft of the'chain driving sprocket 5. A suitable clutch 21, operated by handle 22` is arranged to connect and disconnect the pinion 19 to and from the vertical driving shaft 1H on which it is mounted. This is ,the main clutch for starting the cutter chain` or stopping it when it is-desired to operate other parts of the mechanism without movplaced, as shown, in an intermediatenom.

engaginr position midwayV between them. When t e clutch is moved toward and engaged with the gear 16 the shaft25 and worm 26 are driven directly from the gear 14 in the'same direction-as that gear` re'- volves, and when said clutch is moved toward and engaged with the gear 23 the shaft' 25 and woriii 26 are driven in an opposite direction through the intervening gear V17.

The worm wheel 27 is secu red to a vertical shaft 30 which rotates in bearing 31 and. 32, and carries the spnocliet orchain wheel33 whichengages the feed chain 34. by means ofwhich the mach'rne is advanced along the face of the mineral. In the o eration of the machine the front end of sai feed chain 34 is secured to a jack or anchor 35 set close to the face of the mineral some distance in ad- Vance of the machine, while its rear end is lInt the sumping-in secured to a jackl 36 which will be set up near the face of the mineral when making cut, so that during the undercutting Vit is in the rear of the machine. The machine so far described is not in principle different from certain types of machine now in use for nndercutting coal. It isonly one type of machine which is adapted for carrving out the method of the present invention. Any type of machine which is used must provide meanswhereby it can besuccessively angled clockwise and contra-clockwise and whereby the rate of forward 4feed can be varied, so as to produce a substantiall uniform cuttingl action at all times.

lie machine of Figs. 4, 5, 6 and 7, these effects are produced by the following means:

Just in advance of the feeding wheel 3 and preferably substantially in line With'the rear edge thereof, is a movable idler sheave 38 mounted on the outer end of the long arm of a lever 39 fulcrumed at 40 and carrying a nut 41 engaged by screw 42 for moving the sheave 38 toward and from the feeding wheel 33, t9 increase or decrease the rate of paying out of the rear or check portion of the feed chain 34, and thereby vary the angular position of the machine. The variation in the forward feed o'f the machine is secured by varyin the rate of winding in the forward end o the feeding chain. his, in the form of machine shown in Fig. 4, is accomplished by leading the forward end of said chain over an idler sheave 43 journalled to the machine frame, thence over an idler sheave 44 carried on the inner short arm of the lever 39, and thence over another idler sheave 45 mounted on the machine frame. When the lever 39 is swung in one direction it decreases the payin out move- .ment of the rear or check end o the feeding cham,- and simultaneously decreases the winding in movement of the forward end of said chain, and when said lever is swung :in the opposite direction the opposite ell'ect is produced. If the Alever arm on which the sheave 38 is mounted was equal in length to the lever arm carrying the sheave 44 the equal movement of both sheaves and the only result would be to equally decrease o'r equally increase the rate of paying out and windin in movements of the two ends of the cab e.' But by making the inner arm of lever 39 shorter than the outer arm a differential actioni's allowed whereby the change in the rate ofthe paying ont movement is always greater than the change in the rate of the winding in movement, and a combined angling and `accelerating (or retarding) movement is obtained. T'husI Vif the lever 39 is moved in a direction to carry the idle sheave 38 away from the feed wheel 33, that is, tow-ard the right in Fig. 4, the machine is angled contra-clockwise and at the same time its forward feed 'is decreased; and if said lever isswung inthe opposite direction, so as to cause the idle sheave 38 to approach the feed wheel 33, the niachine is angled clockwise and the forward feed is accelerated. 4 i

As shown, the lever is oscillated from a cam 47 carried by the worm wheel 27, and engaging a roller 48 on one end of the s ring controlled lever 49 fulcrumed at 50, an having its op 'ositeend connected by link or other suita le means 51 with an oscillatory angle-shaped frame 52 mounted on the end of shaft 25 concentric with a pinion 53 se! cured to said shaft 25 and rotatin, there,

with. Pinion 53 meshes directly witA a relatively large gear 54 mounted in the oscillatory frame 52 and indirectly through an yidler 55 with a smaller gear 56 also mointed in said oscillatory frame. The parts are so arranged that only one'of the gears 54 or 56 can be vsimultanecmsly in engagement with ear 57 on the screw shaft 42. The cam 4 has a high portion 58 which holds the gear 54 in mesh with geit-r 57, and a low portion 59 which allows the spring on the lever 49 to bring the gear 56 in mesh with gear 57. In the operation of the machine the frame 52 is rocked alternately in opposite directions, thereby driving the screw 42 alternately in opposite directions and oscillating lever 39 alternately in opposite directions to either simultaneously but differentially h the rate of movement of the feed and check portions of the`chain to and from the machine thereby either accelerating the feeding speed while permitting the machine n movement of the leverV 39 would result in an v1225 increase or decrease to angle clockwise, ,or reversely retarding the forward feeding movement )vhile angling the machine contra-clockwise, By this mechanism, therefore, Vthe angular position of the cutter bai'. with' referenceto the line 1c angling by -properly proportioning the len h of the lever arms carrying the idle s eaves 38 and 44. FigsA 8, 9 and `machine in which the oscillating 'lever 39 rand idle sheaves' 38 and 44 carried thereby 0 wheel or rope drum 61.

5 the screw 42.

fi li) 5 the increase in the are dispensed with. In this case the cha-in or rope 34 passes irectly from'stationary idler sheave 43 on thepmachin'e frameto a second idler sheave oh thema-chine frame, thence around chain wheel or rope drum 61 and over guide sheave 62 to the rear jack. The wheel 61 is driven .in the same manner as in Fi 4 from worm 26 engaging worm wheel 27a The wheel, 61, and worm wheel 27, rotate on a. heavy stud, mounted on a carriage 63 slidable in ways 64 in the frame, said carriage having an in teriially threaded member 42" engaged by When this. screw is rotated so as to move the wheel 61 toward the-right, viewing Fig. 8. a ull will be exerted on the rear or check en of the chain 34, thereby angling the machine contra-clockwise. movement also caiises the chain wheel 61 to rotate clockwise (or in the 'opposite direction to the rotation being im arted thereto by the worm 26B) due to the act that the worm wheel 27 must roll along the surface of worm 2G, which is made suiiicienly long to permit the necessary movement. The forward rolling movement of the' worm wheel 2T on the worm 26* while the latter is revolving thus results in a decrease in the angirlar velocit \1 of the wheel 61 and since the wheel 6l is of materialliy greater diameter than the worm wheel 27a this decreased angular movement results in a material periphcralretardation of theI inner edge of the. wheel with respect producing to the outer edge, thereby a differential eliect on the ratzio of paying out and winding in of the rear and front ends of the feeding chain 34. and thereby securing the necessary decrease in the forward feeding movement of the machine while the machine is angling contraclockwise. which is required to secure uniform cutting action. When the chain wheel 61 is moved in the opposite direction exactly the opposite effect is secured. that is to say. rate of paying out of the 10 show a modified form of4 secured to the hub of the chain' This rear or check end. of the feed chain-which permits the machine to angle c loekwisef-is greater than the increase in the rate of taking up oijwinding in of the forward end of said chain which results in an accelerated forward movement of the machine.

In this case as before it wilLbe notedithat I the simultaneous or co-operating angling andfeed accelerating (or retarding) movements are effected by simultaneously but differentially accelerating or retardi'ng the4 s ed atvwliich feed and cheek portions of t e chain or cable 34 are respectively wound in and paid out; the variation in the rate 'of movement of the former being always less than that of the latter.

.ln this form of machine the screw 42 is alternately rotated in opposite directions by the following mechanism:

Mounted on bearings 64 above worm 26 so as to mesh therewith is a worm Wheel 65 carrying a Vcam 66 having high and low portions engaging roller 67 on ever 68 fiilcrumed at 69 and having its opposite'end connected to oscillating frame 52a mounted concentric with pinion 53, which engages directly with a gear 54 and through an idler 55 with a smaller gear 56, said frame and gears being so arranged that'only one of gears 54a or 56a canbe in engagement. simultaneously with gear 57 on screw 42. These parts of the mechanism operate thesame as the corresponding parts in Figs. 4,- 5, 6 and `7 Figs. 11, 12, 13 and 14 show another modified form of machine for carrying out the method. In this machine there are two winding drums, .to wit, driimf'f for the front or feeding cable or rope 34 and'drum 76 for the check cable or rope 34". l These two drums are mechanically independent of each other and are adapted to besimultaneously rotated but in opposite direct-ions so that one of said cables or chains is woim up while the other is being paid'out. The mechanisms for drivin the twoidriimsV are at the opposite ends o the motor, and are the same with the except-ion that the mechanism at the rear or otiter end of the machine has certain additions to that at the inner or forward end. A description of the mechanism at the outer end will Suffice for both. y, The motor 10a is mounted on the frame 6 with itsl armature shiiuld lengthwise of said frame. and` is provided at each end'with a worm 77 meshing with a worm Rvheel78 on a vertical shaft 79 mounted in suitable bearings in the frame. The-wertical shaft 79 at the outer or rear end of the frame carries the pinion 19 which meshes with the master gear 20 of the cutter chain sprocket'. This pinion is of course omitted on the corresponding shaft at the other end of the frame, The shaft 79 also has loose thereon a spur gear 30 which meshes with a larger spur nism for the winding lgear 81 loose on a vertical shaft V82. The

later at this lower endcarriesv a worm 83 meshing with 'a worm wheel ,84 secured to the winding drum- The ai' 81 comprises the -lower member of a di' erential gear, the upper member being formed by a worin gear 85 also loose on shaft 82. The gears 81 a. nd 85 yare provided on their inner faces with beveled gear members 86, with -which mesh the interposed beveled gears 87 carried by the member 88 fixed to the shaft 82. This is an ordinary type of differential gear which will be understood withoutfilrther description. The Worm wheels 85 at the two ends of the machine are engaged respectively by worms- 90 and 91 carried b the longitudinal horizontal shaft 92. Tliese wormsfhave their threads of diii'erent pitches, so that rotation of the shaft 9 2 rotates the differential gear elements 85 ,in such directions as to simultaneously but dietentially 'accelerate or retard the rotary movement of the two winding drums 75 and 76 for a purpose hereinafter described.

As far as described, the driving mechathe 'two ends of the machine are identical except as noted, that is that the vertical shaft 79 at the rear endof the machine carries pinion 19 which meshes ,with the master gear of the cutter chain qirocket. y

The feeding movement of the machine can be started or entirel stopped b means of clutch 93 operated by liever 94 andy serving to lock gear 80 to, or release said gear from the inner or front/vertical shaft 79.. SimilarIy, the movement of the check rope drum can be started or stopped by means of clutch 95 operated by lever 96 and servin to lock gear 80 to, or release said gear rom the outer or rear verticallshaft 79. In order that the movement of this check rope drum may be reversed at certain times,asin suinping rations, etc-the clutch 95 is splined 4to th); rear shaft 79 between apair of reversely arranged bevel pinions 97 and 98 Aloose on shaft 79 and in constant mesh with an in ter ediate idler pinion 99. The bevel or secured to gear 80- The clutch member 95 is arranged to engage clutch faces on either of the gears 97 or 98 and lock either, but not both, to said shaft. When the clutch is engaged with the bevel pinion 98 the check rope. drum is re` volved in such direction as to unwind or a y out the check rope at the saine rate as'A the feedv rope is wound up by the front drum; when the clutch 95 is engaged with the bevel pinion 97 the rear drum is revolved at the same speed but in the op osite direction. The latter movement is not owever utilized while the machine is cross undercutting. It is used only when the machine isbeing employed in sumping in, or

drums 75 and I76 at is being drawn l106.v This clutch lever is adapted` 'to be shifted back and forth to engage said gears alternate] by means of a two mein ers 108 and 109 both pivofed at 115 and a'djustably connected by' the slot and bolt connection 116, said lever at its lower end carrying roller 111 engaging a cam 112 secured to the'axis 130 of winding drum v76. This cam `is .of the same general character as that shown in Fi 7 having a high `part and a low high part being adapted to hold the clutch member 107 in ,en ent with the gear 105 and thereby drive the shaft 92 and dif- ,ferential gears 81, the low, part permitting the spring to throw the clutch .member 107 into engagementiwith the gear 106 and thereby drive the shaft 92 and differential gears 81,` 85 in the opposite direction. i

With this form of machine the feeding cable 34 is wound onto drum 75 while the check cable 341 is simultaneously iinwound from drum 76. If it were not for the ecal mechanjsmdescribed in the preceding paragraph which is provided for the purpose of angling and varying the feed` the one cable would be wound up as rapidly as the other is unwound and a parallel feeding movement obtained thereby. The action of the cam 112 with the connections above described produces vthe necessary angling movement alternately .clock-wise and contraclockwise and also provides for the necessary corresponding acceleration and retardation of the feeding movement so as to secure a substantially uniform cutting action at all times: The gears 80 being constantly in mesh with the lower members 81 of the diil'erentials would. in the event ofthe upper members 85 of said difi'ere'nt-ials remaining stationary, produce a uniform payingout of the check cable und a uniform winding up of the feeding cabV and this effect is produced in case the c iitch member 107 is held in intermediate 105,'tlie shaft. 92 is rotated in one direction, and the upper menibeis 85 of the two differentials are rotate-d in one (and the same) lever comprising 5 in one direction, and' Ithe mine Hoorl between cutting part', the

Iposi-tion. But when the Vclutch 107 is 1n engagement with the pinion direction, say, in a direction to accelerate the rotation 'of shafts 82 and, `therefore, accelerate both the Winding up of the feeding cable Aand the paying out of the checkcable', but in varving degree, due to the difference in pitch o the'worms 90 and 91;-and when l .said clutch 107 is in e gement with the bevel pinion 106, the sha 92 and the upper members 85 of the differentials are in the opposite direction, say, in a direction to retard the rotation of the shafts-92, and again in varying degree, thereby a retardation of the Winding up o the feeding cable and a greater retardation of the paying out of the check cable. 4'Forfthe pro duction of these effects, it is of courl imp material in which direction pinionf103 is rotated, since the clutch is part of the time in engagement with the pinion 105 and for the other part in engagement with the pinion 106, and the necessary retardation and acnately accelerated and retarded.

celeration will be secured irrespective of the direction of the rotation of. pinion 103. In this case, as'in preceding cases it is only necessary that the design of the cam- 112,-- i. e. the relative lengths of the high and 10W portions of said camshall be such as to equalize the angular swinging movements of the machinein the two and contra-clockwise, while the drum 76 to which the ram 112 is secured is being alter- Any de' sireil ratio between the feeding and 'the angling movements may bewallowed by varying the pitches of the worms and 91.

. In order that "fhis effect may be prolucegl by hand, `iLhe clutch 107 is also arranged for hand sifting. Tothis end, the arin 10) is formed Yin two pivotally connected at 1,15 and1 having a releasable connection at 116, such as a bolt on one member extending through an arch shaped slot on the other member'. -When this bolt is tightened up, the tivo members become a rigid arm and the clutch is shifted from cam 112; But when the bolt 116 is released, the cam no longer eects the clutch. The clutch can then the following means: extended und on its end is provided with u. crank or handle 118 by means of which rod 115 can he oscillated and the clutch shifted as stated (sce Figs. 14 and 11).

All of the automatic machines above described operate on the same general principles and they ae all obviously adapted to secure the necessary relation between the angling movements and the variation in the feeding movements that are diagrammatically illustrated in lig. 1; in which, it will he observed. when the machine is angling contra-clockwise. there is a retardation not only of the feeding movement but also of the payingr out of the check cable; while when said machine is angling clockwise,

livot rod 115 is B; constantly changing mac i and with a less expenditure of power than where the cutter moves continually parallel with roducing directi ns.` clockwise be shifted by hand by- Inveither form the properly proportioning the derential rates and angling movements can besecured.

the anglev of the ne. or the angle ofthe cutter relative to the face on which the cutter is acting,

the speed of cutting is very greatly increased the samev amount of mineral can be cut itself, as is the usual practice. This zig zag. method of uridercutting'has the further advantage of enabling the machine to cut runder or cut out hard nodules more readily and easily than when the line of the cpt is kept unaltered. To attain the advantages of this method itis not necessary to oscil late tHe' cutter bar equally on both sides of a normal to the line of advance. In some cases it maybe advantageous .to swing the Vmachine back and forth unsymmetrically with'respect to'that line; i. e. to swing .1t in such a way that in'one extreme angular position it is more inclined to the face of the mineralor the line of advance-than it is in its other extreme angle position. This can be readily accomplished with anycf the automatic machines above describedas well as by hand-at any time during the 'cut by stopping the machine, disengaging the automatic shift mechanism and moving the angling mechanism, independently of the feed mechanism. Then on reengaging the automatic shift mechanism and restarting the machine the. operation will go.on as be fore save that the machine frame in its osci lating angling movements will now swing around a new mean-angular position to the vface of the mineral or the line of the cut.

As. will now be readily appreciated by those skilled in the ait the method can be carried out by various other forms of machines than those herein described and illustrated, either of the cutter chain type, cr the, rotary cutter bar type. By the-term cutter bar in the claims it is int/ended to covereither a cutter barawth a chain cutter, such as illustrated, or a rotary bar provided with cutters arranged along its length. axis of the cutter bar eve tends parallel to the face of the out.

By the term cable in the claims hereinafter made, it is intended to include any form of cable,either a Manila rope. a wire ro e or cable, or a chain cable. Vhat I claim is:A

l. In a ctter bar mining machine, the :ombination of a .mechanism for continu- .ously feeding and guiding the machine bodily along a coal face, and means acting automatically on the feeding'and guiding mechanism While the machine is continu- 'of variation o f4 these two movements any desired ratio between feeding Hifi ously advancing for vary-ing the .rate of the feed and simultaneously varying thc angular position of the cutter bar.-

2. ln a cutter bar mining machine, the combination of a mechanism for guiding and continuously feeding the maihine along a coal face. and means acting automatically on said feedingjind guiding mechanism for oscillating the axis of the cutter bar alternately in opposite directions clockwise and contra-clockwise while the machine as an entirety' is bodily advancing to vary the angular' relation of the said bar `to the coal face and simultaneously retarding the feed4 .of said bar when the machine 1s swinglng each element independently for auto-matically increasing or diminis 1g the rate at which the. elements are respectively drawn in andV paid out by said driving mechanism whereby the angular position of the machine frame is varied and simultaneously the rate of feed is also varied.-

4. A feeding and guiding mechanism for a mining machine comprising in combination, two cable elements adapted to have their ends attached to xed points of support, a driving mechanism on the machine adapted to have continuous operative engagement with said elements. and automatically opcmtedmeans engaging the cable elements scparately'for simultaneously increasing or simultaneously diminishing the rate at which said elements are respectively drawn in and paid out hy said driving mecha-nim, whereby the angular position of the machine is varied and simultaneously therewith the forward feed of the outer part of the machine is varied in a` manner to accelera-te the said fee-d when the machine is angled clockwise and to retard said feed when the machine is angled contra-clockwise.

v.5. A feedin and guiding mechanism for a. minding mac ine having an outer frame clement and a forward projecting cutter elcment'comprising in combination, two cable elements adapted to have their free ends attachedV to fixed points of support, driving mechanism on the machine adapted to continuously engage operatively with said elements` and anautomatically operated differential mechanism engaging with both of ously decrease or simultaneously increase' therates of effective movements of said elements respectively between said driving mechanism Vand both of said fixed points of support.

6. A feeding and guiding mechanism for a mining machine having an outer frame element and' aA forward projecting cutter bar, comprising in combination, two cable elements adapted toliane their free ends attached to fixed abutn` ts` driving mechanism on the machine adapted to continuously engage operatively with both of said elements. and an automatically operated differential mechanism engaging with both of said elements and arranged to swing the cutter bar contra-clockwise a predetermined distance with accelerated speed and then swing the frame with/acceleratedispeed and move the bar relatively clockwise with retai-ded speed. y l

7. A feeding and guiding mechanism for a mining machine. comprising in combination, two cable elements adapted to' have their free ends attached to fixed ends of support, a driving mechanism on the ma-` chine adapted to continuously engage operatively with said elements, and an automatically operated diflerential mechanism enga rim1r with both of said elements. said parte icing arranged to have the bar swin contra-clockwise with accelerated spee while the frame is advancing with retarded speed, and then to advance the frame with accelerated speed while the bar is advancing with retarded speed and caused to swing -relatively clockwise.

In testimony whereof, I have hereunto set my hand.

FRANK L. 0. WADSWURTH. Titnesses ELunn'r L. HYDE, WILLIAM B. WHARTUN.

60 said elements and arranged to simultane- 

